1. Technical Field
The present invention relates to a liquid ejecting head and a liquid ejecting apparatus, and specifically, to an ink jet type recording head and an ink jet type recording apparatus in which ink as liquid is discharged.
2. Related Art
A representative example of a liquid ejecting head discharging liquid is an ink jet type recording head discharging ink. In the related art, as an ink jet type recording head, there is known a the recording head including a head main body which has a manifold in which liquid is retained, takes ink in a pressure generation chamber communicating with the manifold, deforms the pressure generation chamber with a pressure generating unit such as a piezoelectric element and then discharges liquid from nozzles.
In the ink jet type recording head described above, a compliance substrate absorbing a pressure change inside the manifold and a compliance space which is a space of the degree not to inhibit the deformation of the compliance substrate are provided. Thus, a recording head having an atmosphere opening path which communicates the compliance space with the outside has been (for example, see, JP-A-2011-056872). When the compliance space is closed, the compliance substrate is difficult to deform due to an increase of a pressure inside thereof and the deformation of the compliance substrate cannot be inhibited by communicating the compliance space with the outside.
Moisture included in ink evaporates and penetrates the compliance substrate and thereby enters the compliance space. When the compliance space communicates with the outside, the tendency thereof is strengthened. In other words, moisture of ink inside the manifold easily evaporates and as a result, viscosity of ink inside the manifold increases. When the viscosity of the ink increases, there is a concern that printing quality may be decreased such as failure of discharging of ink and occurrence of gradation difference in the density of ink which is printed.
In the ink jet type recording head disclosed in JP-A-2011-056872, a control path having high path resistance is provided at the atmosphere opening path and thereby a passing amount of water vapor is suppressed and it is suppressed that liquid becomes water vapor and spreads from the compliance substrate.
However, when the atmosphere opening path dries, moisture of ink inside the manifold further easily evaporates and there is a concern that increase of the viscosity of ink may not reliably prevented. In addition, even though the control path is provided, the control path having a sufficient path resistance may not be provided according to the configuration of the ink jet type recording head, position, size and configuration of the atmosphere opening path or the like.
In addition, such a problem similarly exists in a liquid ejecting apparatus ejecting liquid other than ink.